updated 11:21 am EDT, Tue October 1, 2013

Talks to continue later this month

Carl Icahn pushed for an expanded, $150 billion Apple share buyback during his dinner with Tim Cook yesterday, according to a Twitter post by the influential investor. "Had a cordial dinner with Tim last night," Icahn wrote. "We pushed hard for a 150 billion buyback. We decided to continue dialogue in about three weeks."

Apple is already in the middle of a buyback plan that will cost it $60 billion by the end of 2015. Icahn, however, has argued that Apple shares are undervalued, and that the plan could grow further. He has a significant profit motive in increasing buybacks, since he recently invested about $1.5 billion in the company. News of the transaction briefly sent Apple shares back over the $500 mark.